1. Field of the Invention
The present invention relates to a capacitor device that is used together with a battery, and a vehicular power supply device.
2. Description of the Related Art
In general, in a case where a battery, such as a lead-acid battery, installed in a vehicle such as a gasoline-driven car or a diesel vehicle, is configured to have a large electric capacity so that a large amount of power can be instantaneously output, its installation functionality deteriorates. Capacitors, such as a lithium ion capacitor and an electric double layer capacitor, instantaneously charge and discharge a large amount of power. However, such capacitors have a storage amount lower than that of lead-acid batteries.
Accordingly, a vehicular power supply device (see, for example, Japanese Unexamined Patent Application Publication No. 6-270695) that can instantaneously output a large amount of power by combining a battery and a capacitor without enlarging entire size is known.
In a case where, in a vehicular power supply device of the above type, a battery or the like enters an over discharge state (so-called battery-dead state) due to a vehicle not being used for a long period of time, in general, similarly to a power supply device including a single battery, power is externally supplied to the vehicular power supply device via a booster cable or the like. However, for a power supply device in which both a battery and a capacitor are used, sufficiently careful handling is required since such a power supply has a current inflow amount much larger than that of a power supply device including a single battery.
In addition, in particular, a capacitor is configured to instantaneously charge and discharge a large amount of power. Accordingly, for example, in a case such as when a capacitor that remains charged is mounted to or demounted from the vehicle, sufficiently careful handling is required.